Abstract
Recently, several clinical trials in acute stroke have failed to produce efficacy. This suggests that there is a large gap between results in human trials and in animal. Animal models may present on aspect of pathophysiology in patients. We have to know how similar and what aspect of animal models can be extrapolated to patients. It is a big question whether or not therapeutic time window between animal models and patients is similar. In some animal models, cerebral damage establishes within 6 hours of the MCA occlusion, and this indicates that it is impossible to cure cerebral damage when drug injection is administrered over a 6 hour pe-riod. Recently, some investigators demonstrated that in human penumbra disappears within 6 hours after ischemia and therapeutic time window is as narrow as that in animal models. Finally, in animal studies, effects of neuroprotective agents are evaluated by the size of cerebral damage and neurological deficits. In human trials, effects of these agents are evaluated by stroke scores in including Japan stroke scores. In stroke scores, consciousness, language ana paralysis are examined, but in animal models, only paralysis is examined. Data of neurological symptoms of animal studies do not accord with those in human trials.
